Stabilized polyvalent metal soap composition

ABSTRACT

A hydrocarbon solution of a hydrolizable manganese soap, by inclusion of propionic acid, in amounts of about 5 percent - 10 percent in the total solution for usual manganese content, is markedly stabilized against hydrolysis of the soap and from consequent precipitation of the metal content from solution, especially by stabilization against formation of an emulsion with water, and thereby is effectively preserved from hydrolysis; thus, for example, in the case of fuel oils preventing difficulties in pumping, or ultimately at the burner due to sputtering, which can result from emulsification and/or precipitation; with manganese neodecanoate solutions of varied manganese content, a propionic acid/manganese weight ratio of at least about 1.0.

United States Patent 1191 Collins 1 Oct. 2, 1973 STABILIZED POLYVALENT METAL SOAP 221 Filed: Feb. 28, 1972 [2l] Appl. No.2 230,141

[52] US. Cl..... 44/66, 44/68 [51] Int. Cl C101 1/18 [58] Field of Search 44/68, 66; 252/35,

[56] References Cited UNITED STATES PATENTS 3/1947 I Melennan..... 252/35 2,225,366 12/1940 'Bray 252/35 3,055,829 9/1962 Wiley et al.... 252/35 2,920,047 1/1960 Hyatt et al. 252/340 3,424,565 l/l969 Ptacek et al 252/340 Primary Examiner-Daniel E. Wyman Assistant ExaminerY. H. Smith Att0rney-Philip D. Golrick et al.

[57] ABSTRACT A hydrocarbon solution of a hydrolizable manganese soap, by inclusion of propionic acid, in amounts of about 5 percent 10 percent in the total solution for usual manganese content, is markedly stabilized against hydrolysis of the soap and from consequent precipitation of the metal content from solution, especially by stabilization against formation of an emulsion with water, and thereby is effectively preserved from hydrolysis; thus, for example, in the case of fuel oils preventing difficulties in pumping, or ultimately at the burner due to sputtering, which can result from emulsification and- /or precipitation; with manganese neodecanoate solutions of varied manganese content, a propionic acid/- manganese weight ratio of at least about 1.0.

7 Claims, No Drawings STABILIZED POLYVALENT METAL SOAP COMPOSITION Polyvalent metal soap compositions in quite large variety in the metal and acid moieties of the individual soap compounds, in mixtures of soaps, in the vehicles or carriers, and in additives for other specific functions, have come into commercial production and extensive use, particularly as siccatives for paints, varnishes, inks; as stabilizers in diverse plastics; as additives for grease and lubricating oils; as additives for fuels and fuel oils usually either for smoke abatement or anti-corrosion purposes.

In some fields of use, compositions containing these soaps are subject to contact with water, either in storage or field handling of a composition itself, or perhaps after incorporation in some other substance such as fuel oil. Contact with water, if extensive either in duration or in interfacial area, may lead to a hydrolysis of the soap and a corresponding precipitation of the metal in an insoluble simpler compound, such as an oxide or hydroxide, thus rendering the metal at least unavailable for its intended purpose, if not engendering other problems, as a solid in a liquid storage or handling system.

Thus for example, manganese soap compositions such as manganese neodecanoate, or mixed manganese neodecanoate and other manganese branched chain carboxylates, in solution in light mineral oil or mineral spirits, are useful additive compositions in fuel oils. However, these compositions emulsify with water and in consequence of the extensive area exposed to water, the total of the interface area of the unnumerable micelles, hydrolysis, of the contained manganese soap substance occurs rather rapidly, resulting in a precipitation of manganese dioxide, thus diminishing the effective, that is dissolved, manganese compound content of the composition.

Further the manganese dioxide may result in undesirable sludging in storage tanks, and in extreme conditions, to possible plugging of nozzles, valves and like operating or maintenance situations. Even the emulsion itself can plug nozzles or valves; and can, upon reaching a burner, cause spattering and extinction of the flame.

It has been discovered that, for example, in such manganese soap compositions, especially manganese neodecanoate, but also with other manganese carboxylates mixed therewith, in mineral spirits or in light mineral oil (especially where the total composition has a comparatively high acid number) the inclusion of propionic acid in an amount typically comprising percent by weight of the total composition, or say percent of the contained soap weight, results in a notable stabilization of the total composition against emulsification by water, and therewith a marked resistance,

to precipitation of manganese dioxide by water contact. Also it has been found that when manganese naphthenate represents a large major part, with neo cation with water and thereby to hydrlytic precipitation of manganese dioxide.

The neodecanoic acid hereinafter named in the composition examples is a standardized isomeric mixtureo f ten carbon neo acids marketed by Enjay Corporation in commercial quantities, and accordingly the term neodecanoate refers to a product derived from such acid.

The emulsification, hydrolysis and precipitation problem to the abatement of which the present invention is directed is shown by the following comparative Example l, with subsequent examples disclosing the invention, and limiting conditions.

EXAMPLE 1 (COMPARATIVE) By a standard conventional direct metal reaction procedure in parts by weight there were reacted:

acid manganese soap a small part, though emulsions 477 parts of neodecanoic acid,

with 67 parts of ground manganese,

in 419 parts of mineral spirits,

with 2 parts ofacetic acid and 5 parts of water to promote the reaction, and also 40 parts of polypropylene glycol. The resultant manganese neodecanoate solution product, 1,000 parts, containing about 6.0 percent manganese and having an acid number of about 10, when testedby vigorous shaking of a sample with an equal volume of water, emulsified readily, and exhibited heavy .precipitation of manganese dioxide after a few hours standing.

EXAMPLE 2 Again by a standard conventional direct metal reaction procedure as in Example 1, in parts by weight there were reacted:

477 parts of neodecanoic acid,

with 6] parts of ground manganese,

in 323 parts of light mineral oil,

with 2 parts of acetic acid and 5 parts of water to promote the reaction, and also 40 parts of polypropylene glycol. Toward the end of the procedure (after substantially complete reaction of the acid with the metal) parts of propionic acid was admixed. The filtered resultant product adjusted with oil for volatile losses to 1,000 parts, containing about 6.0 percent manganese,

in the form of dissolved manganese neodecanoate soap,

10 percent propionic acid, and having an acid number of 72 and suitable as an additive to power plant boiler fuel oil for smoke abatement, was found to be quite resistant to emulsification and precipitation. After vigorous shaking with an equal volume of water, the phases separated rapidly with but a trace of residue at the interface. The weight ratio of propionic acid to manganese here is 1.67.

EXAMPLE 3 A composition prepared similarly to Example 2 with 630 parts of neo decanoic acid, 81 parts manganese, in

73 parts of the oil, with 7 parts water, 3 parts acetic acid, 53 parts polypropylene glycol, but with 133 parts propionic acid, gave stability results identical to those of Example 2, the product composition containing 8 percent manganese, about 13 percent propionic acid, and having an acid number of 96. Again the propionic acid-manganese ratio is 1.67.

EXAMPLE 4 PROPlONlC ACID EFFECT In a manner similar to Examples 2 and 3, there were made up and then tested manganese neodecanoate product solutions adjusted to 6 percent manganese content, with the amount of diluent oil varied to accommodate the changes in propionic acid percentage content for ratios of propionic acid to manganese, as follows:

Propionic Ratio Emulsion 24 Hour Acid Propionic with Precipi- Acid/Mn Water tation by Water 2.0 0.33 moderate moderate 5.0 0.83 moderate moderate 6.0 b L none slight 7.25 1.21 none none 8.0 L33 none none 9.0 l.50 none none I00 I67 none none 25.0 4.l7 none none Here 10 gram test specimens were each vigorously shaken for 30 seconds with 90 grams of tap water in a capped 4 ounce bottle and examined for demulsification after standing 2 minutes and for presence at the interface of manganese dioxide precipitation after 24 hours. When the interface was clear and clean and there was no emulsion phase present after 2 minutes standing (considered not as forming an emulsion and designated None" in the above table and in prior examples), and no precipitation even at the interface, the specimen was considered stable against emulsification and precipitation by hydrolysis, and hence a satisfac tory product under this invention.

Similar results were obtained for similar ratios of propionic acid to manganese with both the volatile and non-volatile hydrocarbon solvent, with varying minor amounts of polypropylene glycol for viscosity adjustment, and with other manganese neodecanoate concentrations. Although the tendency to form an emulsion and a precipitate was reduced even at the lower ratios, a minimum propionic acid to manganese weight ratio of about 1 evidently is required to confer the desirable property of stability against emulsion formation and hydrolysis-caused precipitation.

No specific upper limit to the discussed ratio appeared' except to the extent that increased propionic acid might affect other desired properties of the particular solution by requiring say less solvent to be present to maintain other nominal values.

I claim:

1. A homogeneous liquid composition comprising:

a hydrocarbon liquid and a manganese fatty acid soap having more than 4 carbon atoms dissolved therein, and

propionic acid in an amount effective to stabilize the composition against emulsification with water and hydrolysis-caused precipitation of manganese dioxide.

2. A composition as described in claim 1, wherein said soap is manganese neodecanoate.

3. A composition as described in claim 1, wherein said hydrocarbon liquid is mineral spirits or light mineral oil.

4. A composition as described in claim 1, wherein said soap is manganese neodecanoate, and

said hydrocarbon liquid is mineral spirits or light mineral oil.

5. A composition as described in claim 4 containing from about 6 to 10 percent by weight manganese as the neodecanoate, and a minimum of from about 10 to l3 percent by weight of propionic acid.

6. A composition as described in claim 5 including at least about 4 percent by weight of polypropylene glycol.

7. A composition as described in claim 4, wherein said propionic acid is present in an weight ratio of acid to manganese of at least about 1.0 

2. A composition as described in claim 1, wherein said soap is manganese neodecanoate.
 3. A composition as described in claim 1, wherein said hydrocarbon liquid is mineral spirits or light mineral oil.
 4. A composition as described in claim 1, wherein said soap is manganese neodecanoate, and said hydrocarbon liquid is mineral spirits or light mineral oil.
 5. A composition as described in claim 4 containing from about 6 to 10 percent by weight manganese as the neodecanoate, and a minimum of from about 10 to 13 percent by weight of propionic acid.
 6. A composition as described in claim 5 including at least about 4 percent by weight of polypropylene glycol.
 7. A composition as described in claim 4, wherein said propionic acid is present in an weight ratio of acid to manganese of at least about 1.0 